<TITLE>unsetenv</TITLE>
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<h3>SETENV(3)           Linux Programmer's Manual           SETENV(3)
</h3>

<h3>NAME
</h3>       setenv - change or add an environment variable

<h3>SYNOPSIS
</h3>       #include &lt;stdlib.h&gt;

       int setenv(const char *name, const char *value, int overwrite);

       void unsetenv(const char *name);

<h3>DESCRIPTION
</h3>       The  setenv() function adds the variable name to the envi-
       ronment with the value value, if  name  does  not  already
       exist.   If  name  does exist in the environment, then its
       value is changed to value if  overwrite  is  non-zero;  if
       overwrite  is zero, then the value of name is not changed.

       The unsetenv() function deletes the variable name from the
       environment.

<h3>RETURN VALUE
</h3>       The  setenv()  function  returns zero on success, or -1 if
       there was insufficient space in the environment.

<h3>CONFORMING TO
</h3>       BSD 4.3

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<h3>SEE ALSO
</h3><p>
<a href=getenv.htm>getenv</a>, 
<a href=putenv.htm>putenv</a>, 
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<h3>BSD                       April 4, 1993                         1
</h3>

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